<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>绝对定位脱标</title>
  <style>
    .box {
      position: relative;
      width: 245px;
      height: 245px;
    }

    .logo {
      position: absolute;
      bottom: 5px;
      /* 1. 向左移动父盒子宽度的 50% */
      left: 50%;
      /* 2. 用负的 margin-left 向右移动图片宽度的一半 */
      margin-left: -40px;
      border: 3px solid #fff;
      border-radius: 50%;
    }
  </style>
</head>

<body>
  <div class="box">
    <img src="./images/card_1.gif" alt="">
    <img src="./images/logo_1.jpg" alt="" class="logo">
  </div>
</body>

</html>